“If you are early in your career, you are making a grave mistake not being back at work,” Griffin said Monday in a conversation with Bloomberg’s Erik Schatzker at the Economic Club of Chicago. “It’s incredibly difficult to have the managerial experiences and interpersonal experiences that you need to have to take your career forward in a work-remotely environment.”

Griffin, who runs Citadel’s hedge fund business and Citadel Securities, also said working outside the office hinders innovation and indicated it may hurt the country’s competitiveness. Workers in China have returned “literally from almost the start” of the pandemic, he said.

“So for our youngest members of our workforce, I’m gravely concerned that the loss of early career development opportunities is going to cost us dearly over the decades to come,” he said.

Citadel was among the first hedge funds to allow employees to come back into the office on a voluntary basis—some returned as early as June 2020. Citadel is also among the few firms that aren’t mandating staff be vaccinated. Still, almost all Citadel staff are already vaccinated and back at their desk five days a week.

Griffin said many employees in Corporate America haven’t returned because their bosses are afraid to tell them to do so.

“If you talk to other CEOs, they live in fear of how we’ll be publicly persecuted from delivering the straightforward message: It’s time to go back to work,” he said.

Griffin said that message needs to come from the top and he urged President Biden to address it.

“We need it for our government workers, we need it for our corporate leaders,” he said. “We as a country, it’s time to get back at it.”

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